Pitches pyrolysis kinetics: non-isothermal heat treatments, experiments and model

The present study was focused on the modelling of experimental pitches evolution data obtained under non-isothermal heat treatment. The model, previously proposed for isothermal heat treatment, was based on phenomenological basic mechanisms as gas–liquid, liquid–liquid mass transfer and chemical reactions with respect to the γ, β and α-resins weight fractions assimilated to basic equivalent chemical species. It has been extended to non-isothermal conditions and successfully applied to experimental data for A240 petroleum pitch at four final temperature levels (673, 703, 723, 743 K) and eight heating rates (0.5, 1, 2, 3, 3.5, 4, 4.5, 5 K min−1). The identified kinetic parameters were found to be in agreement with values encountered in literature for similar basic phenomena. This led to an accurate predictive tool intended for reactor design and optimisation taking into account the whole heat treatment process including the non-isothermal step.